Multifunctional scaffolding and pushcart convertible utility device

ABSTRACT

A multi-functional utility apparatus that is convertible between a scaffold configuration and a pushcart configuration. A pivotal coupling assembly between first and second subframes allows the subframes to be expanded for use as a scaffolding or collapsed for use as a pushcart.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/419,437 filed Dec. 3, 2010 and U.S. Provisional Patent Application Ser. No. 61/418,733 filed Dec. 1, 2010, the entireties of which are hereby incorporated herein by reference for all purposes.

TECHNICAL FIELD

The present invention relates generally to the field of construction equipment, and more particularly to a multifunctional utility device that functions as a pushcart in one configuration for transporting objects, and that can be converted to scaffolding in a second configuration for elevated personnel access.

BACKGROUND

Construction projects generally require a number of tools and/or materials that must be transported to the job site. Manually carrying items to the jobsite can be cumbersome and inefficient, and as such, wheeled transport devices such as carts and wagons are commonly utilized. Additionally, in many construction projects, scaffolding is utilized to accommodate the worker for accessing a particular elevated worksite. Some examples include installing drywall, performing electrical work, and painting in elevated areas such as the ceiling or high walls of a building.

Many known scaffolding systems have many components that must be transported to the job site and assembled by at least two workers. Thus, not only are the tools and materials for carrying out the job required to be transported to the jobsite, but also the scaffolding for accessing the work area. Additionally, height adjustments of many known scaffold designs necessitate two or more people and may become extremely time-consuming. In some instances, the physical demands of transporting tools, materials and equipment to and from the job site can exceed the effort required for the actual construction project itself.

Accordingly, it can be seen that needs exist for improved equipment and methods for transporting tools, materials and equipment to a job site, and for accessing an elevated work area. It is to the provision of a multifunctional utility device meeting these and other needs that the present invention is primarily directed.

SUMMARY

In example embodiments, the present invention provides a multifunctional utility device for transporting tools, materials and equipment to a job site, and for accessing an elevated work area. In example forms, the device is convertible from a pushcart configuration to a scaffold configuration. In this manner, the invention enables a user to transport tools and materials to a jobsite while in the pushcart configuration, and easily converts to a scaffolding configuration in a single-person procedure without the need for special tools to access an elevated work area. The invention thus eliminates the need for separate transport and scaffold equipment, and eliminates the need to transport scaffolding to the jobsite, as the equipment used to transport other tools and materials becomes the scaffolding.

In one aspect, the present invention relates to a multifunctional utility device. The device preferably includes a support platform, a first subframe assembly, and a second subframe assembly. The first and second subframe assemblies are convertible between a first configuration forming a scaffolding with the support platform in an elevated position and a second configuration forming a pushcart with the support platform in a lowered position.

In another aspect, the invention relates to an apparatus convertible from a rolling carrier to an elevated support structure. The apparatus preferably includes a support platform, first and second outer subframes, and a central subassembly. The central subassembly pivotally couples the first and second outer subframes and allows the first and second outer subframes to move between a rolling carrier configuration wherein the support platform is positioned at a first elevation and an elevated support structure configuration wherein the support platform is positioned at a second elevation higher than the first elevation.

In still another aspect, the invention relates to a convertible pushcart/scaffolding apparatus. The apparatus preferably includes a first subframe assembly having a first pair of generally parallel siderails and a first plurality of rungs extending between and generally perpendicular to the first pair of siderails. The first subframe assembly preferably also includes a first pair of axial caster wheels extending axially from ends of the first pair of siderails. The apparatus preferably also includes a second subframe assembly having a second pair of generally parallel siderails and a second plurality of rungs extending between and generally perpendicular to the second pair of siderails. The second subframe assembly preferably also has a second pair of axial caster wheels extending axially from ends of the second pair of siderails, and side caster wheels extending transversely from the second pair of siderails. The apparatus preferably also includes a central subassembly having first and second subassembly halves, and also having a first hinged connection between the first and second subassembly halves, a second hinged connection between the first subframe assembly and the first subassembly half, and a third hinged connection between the second subframe assembly and the second subassembly half. The central subassembly thus allows the first and second subframe assemblies to be reconfigured between: (a) an expanded configuration wherein the first and second subassembly halves are extended linearly away from one another, and the first and second subframe assemblies are spaced a greater distance away from one another; and (b) a collapsed configuration wherein the first and second subassembly halves are folded together against one another, and the first and second subframe assemblies are spaced a lesser distance away from one another. The apparatus preferably also includes a platform repositionable between an elevated position when the first and second subframe assemblies are configured in the expanded configuration, and a lower position when the first and second subframe assemblies are configured in the collapsed configuration.

These and other aspects, features and advantages of the invention will be understood with reference to the drawing figures and detailed description herein, and will be realized by means of the various elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following brief description of the drawings and detailed description of the invention are exemplary and explanatory of preferred embodiments of the invention, and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an apparatus according to an example embodiment of the present invention, in a scaffolding configuration.

FIGS. 2A-2E show an apparatus according to an example embodiment of the present invention, in a scaffolding configuration, and showing a sequence of disassembly and conversion to a pushcart configuration.

FIG. 3 shows an apparatus according to an example embodiment of the present invention, in use by a workman in a scaffolding configuration.

FIG. 4 shows an apparatus according to an example embodiment of the present invention, in use by a workman in a pushcart configuration.

FIG. 5 shows an apparatus according to an example embodiment of the present invention, in an upright collapsed configuration.

FIG. 6 shows installation of a slidably installed platform onto an apparatus according to an example embodiment of the present invention, in a scaffolding configuration.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

The present invention may be understood more readily by reference to the following detailed description of the invention taken in connection with the accompanying drawing figures, which form a part of this disclosure. It is to be understood that this invention is not limited to the specific devices, methods, conditions or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example only and is not intended to be limiting of the claimed invention. Any and all patents and other publications identified in this specification are incorporated by reference as though fully set forth herein.

Also, as used in the specification including the appended claims, the singular forms “a,” “an,” and “the” include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” or “approximately” one particular value and/or to “about” or “approximately” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another embodiment.

With reference now to the drawing figures, wherein like reference numbers represent corresponding parts throughout the several views, FIGS. 1-7 show a multifunctional utility device or apparatus 10 according to an example embodiment of the present invention. The multifunctional utility device 10 is convertible between an expanded configuration for functioning as an elevated support structure such as a scaffold 20 and a collapsed configuration for functioning as a rolling carrier such as a pushcart 30. In example embodiments, the device is easily interchangeable between the two configurations by one person or user 5 without the need for special tools, and in some embodiments even without the need for any tools by hand assembly.

In general, the multifunctional utility device 10 comprises a walking or support platform 40, a first subframe 50 a, a second subframe 50 b, and a third subframe 80. In example embodiments, the support platform 40 generally comprises a rigid frame structure 42 having a first end 41 a and a second end 41 b generally opposite thereto, and a planar panel or sheet 44 coupled to a top side 41 c. In the depicted embodiments, the frame 42 comprises four integrally connected elongate members, such as square or round metal tubing members, forming a rectangular frame substantially corresponding to the peripheral contour of the planar panel 44, and the panel 44 comprises a sheet metal, expanded metal, or plywood panel optionally having a non-slip upper surface. In preferred embodiments, one or more bracing members couple within the perimeter of the frame 42 for providing additional structural support. The planar panel 44 is coupled to the top side 41 c of the frame 42 by one or more bolts, pins, screws, weldments, glue, adhesive, or other connectors. The first and second ends 41 a, 41 b have a fin 45 and stationary pin 46 for fixing the support platform 40 to the frame when functioning as a scaffold 20 and/or pushcart 30. The support platform 40 is repositionable onto different rungs 54 of the first and second subframes 50 to allow height adjustment to any of a plurality of elevations when used as a scaffolding by selective engagement of the pins 46 and fin 45 with different rungs. The fins 45 are engaged over a rung 54 of each subframe, allowing the platform 40 to be slid into place and the pins 46 engaged into a receiver opening through the rung to retain the platform in place and retain the scaffold structure in place. In further embodiments, the planar panel 44 comprises one or more handgrips, handles or slots 48 formed therein, thereby enabling the user to easily grasp the support platform 40 when assembling, disassembling and converting from one function to the other.

The first and second subframes 50 a, 50 b each comprise elongated side rails 52 and a plurarity of rungs 54 disposed between the side rails 52, forming a typical ladder construction. In example embodiments, the rails and rungs are square or round metal tubing or rods, affixed by welding and/or bolts or other couplings. The rungs 54 are evenly spaced and coupled along one side of the elongated side rails, providing structural integrity to the subframes 50 a, 50 b. A first end 55 of the rungs 54 includes a mounting hole 58 for receiving the securing pin 46 of the support platform 40 when the device is functioning as a scaffold 20. In the scaffold 20 configuration (FIG. 1), the support platform 40 fits within an interior space formed between the upright siderails 52 of each subframe 50 a, 50 b and is supported along both sides by the rungs 54. Preferably, the rungs 54 are affixed to the inside of the upright side rails 52 such that the outside-to-outside spacing of the rungs when the scaffold is in its expanded configuration is about equal to the length of the platform 40. This allows a single user to place the platform 40 onto the rungs 54 with the fins 45 positioned over the outsides of the rungs (FIG. 6), slide the platform across the rungs into place (similar to sliding an oven rack into an oven), and then engage the pins 46 into holes 58 in the rungs, providing for easy one-man platform installation and height adjustment. Four caster wheels 70 are mounted at a first or lower end 60 of the first and second subframes 50 a, 50 b, and extend axially from each of the siderails 52. These axial siderail end caster wheels 70 allow selective motion and/or maneuverability when the device 10 is functioning as a scaffold 20, and one or more of the caster wheels are preferably lockable to allow movement of the scaffold apparatus when unlocked and prevent movement when locked. The second subframe 50 b comprises two pairs of caster wheels 74 mounted to the elongated side rails 52 and extending transversely outwardly therefrom. These transverse or side caster wheels 74 are preferably positioned on the outside face of the siderails opposite of the coupled rungs 54, one pair toward the first or lower end 60 and the other pair toward the second or upper end, and provide maneuverability when the device 10 is functioning as a rolling carrier such as a pushcart 30. One or more of the transverse or side caster wheels 74 are preferably lockable to allow movement of the pushcart apparatus when unlocked and prevent movement when locked. In alternate embodiments, the functions of one or more of the axial and/or side caster wheels may be combined by pivotally mounting the wheels to the subframe assemblies.

The third subframe 80 of the multifunctional utility device 10 comprises one or more hinge-like swing arms 82. In depicted embodiments, the third subframe 80 comprises four swing arms 82, two coupled to the first subframe 50 a and two coupled to the second subframe 50 b, thus forming a first hinged subframe half and a second hinged subframe half. A first end 83 a of the arms 82 rotatably couples to a tube or sleeve bearing hinge 84 a connected to the rung side of the first and second subframes 50 a, 50 b. The tube or sleeve 84 a receives a pin or shaft extending from the arm 82, and provides a pivotal connection for each arm 82 to rotate relative to the respective first or second subframe 50 to which it is hingedly connected. A second end 83 b of each of the arms 82 is rotatably coupled to a central pivot tube 84 b, joining the first subframe 50 a to the second subframe 50 b. The first and second ends 83 a, 83 b may freely pivot about tubes 84 a, 84 b to expand the device 10 accordion-like to function as a scaffold 20 (FIG. 1) and to collapse the device 10 to function as a pushcart 30 (FIG. 2). When configured as a scaffold, the first and second subframes 50 a, 50 b together with the third subframe 80 form a generally rectangular “U-shaped” or “C-shaped assembly (viewed from above) in the expanded configuration of the scaffold, bounding an enclosed interior space which receives the platform 40. The open front of this assembly, opposite the third subframe and between the first and second subframes, provides access for installation and removal of the platform 40 at any selected rung height, as well as repositioning the platform to different heights by placement on a different selected corresponding pair of rungs 54 at the desired elevation. When the device 10 is collapsed (FIG. 5), as for storage or transport, the second ends 83 b of each arm 82 preferably pivot inwardly into the interior space and the arms nest between rungs 54 for compactness.

In operation, the multifunctional utility device may function alternatively as a scaffold 20 in a first configuration, and as a pushcart 30 in a second configuration. FIGS. 2A-2E show a sequence of conversion of the device 10 between a pushcart 30 and a scaffold 20 as the apparatus is interchanged. The user lifts the support platform 40 to remove the securing pins 46 from the first end of the rungs 54 and slides the platform such that the fins 45 are proximal to the mounting holes 58. The user grasps one or both slots 48 and removes the platform 40 from the rungs 54 (see FIG. 2A). With the caster wheels 70 unlocked, the user folds the third subframe 80 within the first and second subframe 50 a, 50 b. The rungs 54 of the first and second subframe 50 a, 50 b abut each other while the third subframe 80 is folded therein (see FIGS. 2B-2C). The user then lowers the folded subframes in a horizontal position such that the second subframe caster wheels 74 are contacting the ground. Further, the user places the support platform 40 within the rails 52 of the horizontally positioned first subframe 50 a (see FIG. 2D). In additional embodiments, a handle 100 can be coupled to the device 10 (see FIG. 2E). The sequence is reversed to convert the apparatus back from a pushcart to a scaffolding (see FIGS. 4-6). In a scaffold function, the ends of the handle 100 are inserted axially within the interior channel of the second end 62 of the rails 52 of the first subframe 50 a. In a pushcart function, the ends of the handle 100 are inserted within mounting holes 102 proximal to the first end 60 of the first subframe 50 a to retain the handle generally perpendicular to the subframe.

In example forms, the utility device 10 preferably comprises steel tubing generally having a square cross section. In additional embodiments, the device 10 may be formed of aluminum, plastic, composites, wood or other materials, and can comprise oval, elliptical, circular, square or non-symmetrical cross-sectional profiles.

While the invention has been described with reference to preferred and example embodiments, it will be understood by those skilled in the art that a variety of modifications, additions and deletions are within the scope of the invention, as defined by the following claims. 

1. A multifunctional utility device comprising: a support platform; a first subframe assembly; and a second subframe assembly; wherein the first and second subframe assemblies are convertible between a first configuration forming a scaffolding with the support platform in an elevated position and a second configuration forming a pushcart with the support platform in a lowered position.
 2. The multifunctional utility device of claim 1, wherein the first and second subframe assemblies are pivotally coupled to one another.
 3. The multifunctional utility device of claim 2, further comprising a third subframe assembly pivotally coupled between the first and second subframe assemblies.
 4. The multifunctional utility device of claim 1, wherein the support platform comprises a generally planar platform and a support frame, and wherein the support frame comprises at least one pin coupling for attachment of the support platform to at least one of the first and second subframe assemblies.
 5. The multifunctional utility device of claim 1, wherein at least one of the first and second subframe assemblies comprises a parallel pair of siderails having a plurality of rungs affixed between the siderails and generally perpendicular thereto.
 6. The multifunctional utility device of claim 5, wherein the support platform is re-positionable at different elevations by placement of the platform onto selected corresponding pairs of the plurality of rungs.
 7. The multifunctional utility device of claim 6, wherein the support platform can be installed between front siderails of the first and second subframe assemblies, and positioned by sliding the support platform along the selected corresponding pair of rungs.
 8. The multifunctional utility device of claim 1, wherein the first and second subframe assemblies comprise axial caster wheels extending axially from an end thereof.
 9. The multifunctional utility device of claim 1, wherein at least one of the first and second subframe assemblies comprises side caster wheels extending transversely outwardly therefrom.
 10. The multifunctional utility device of claim 1, further comprising a handle that is repositionable from a first handle position generally aligned with the first subframe assembly in the first configuration and a second handle position generally perpendicular to the first subframe assembly in the second configuration.
 11. An apparatus convertible from a rolling carrier to an elevated support structure, the apparatus comprising: a support platform; first and second outer subframes; and a central subassembly pivotally coupling the first and second outer subframes and allowing the first and second outer subframes to move between a rolling carrier configuration wherein the support platform is positioned at a first elevation and an elevated support structure configuration wherein the support platform is positioned at a second elevation higher than the first elevation.
 12. The apparatus of claim 11, wherein the support platform is repositionable in the elevated support structure configuration to a plurality of different second elevations.
 13. The apparatus of claim 11, wherein the central subassembly comprises first and second subassembly halves, and further comprising a first hinged connection between the first and second subassembly halves, a second hinged connection between the first outer subframe and the first subassembly half, and a third hinged connection between the second outer subframe and the second subassembly half.
 14. The apparatus of claim 11, further comprising wheels for allowing movement of the apparatus in the rolling carrier configuration.
 15. The apparatus of claim 11, further comprising wheels for allowing movement of the apparatus in the elevated support structure configuration.
 16. The apparatus of claim 11, further comprising a first set of wheels extending axially from the first and second outer subframes for allowing movement of the apparatus in the elevated support structure configuration, and a second set of wheels extending transversely from one of the first and second outer subframes for allowing movement of the apparatus in the rolling carrier configuration.
 17. The apparatus of claim 11, further comprising a handle positionable generally perpendicular to one of the first and second outer subframes in the rolling carrier configuration.
 18. The apparatus of claim 17, wherein the handle is repositionable to be generally aligned with one of the first and second outer subframes in the elevated support structure configuration.
 19. The apparatus of claim 11, wherein at least one of the first and second outer subframes comprise a pair of generally parallel siderails and a plurality of rungs extending between and generally perpendicular to the siderails.
 20. The apparatus of claim 11, wherein the support platform comprises at least one pin connector for engagement within a corresponding receiver of the first and second outer subframes.
 21. The apparatus of claim 20, wherein the support platform further comprises at least one fin for sliding engagement with a rung of one of the first and second outer subframes.
 22. The apparatus of claim 21, wherein the rung is affixed to an inside face of an upright siderail of one of the first and second outer subframes, and the support platform can be installed between the first and second outer subframes and positioned by sliding the at least one fin along the rung.
 23. A convertible pushcart/scaffolding apparatus comprising: a first subframe assembly comprising a first pair of generally parallel siderails and a first plurality of rungs extending between and generally perpendicular to the first pair of siderails, and a first pair of axial caster wheels extending axially from ends of the first pair of siderails; a second subframe assembly comprising a second pair of generally parallel siderails and a second plurality of rungs extending between and generally perpendicular to the second pair of siderails, a second pair of axial caster wheels extending axially from ends of the second pair of siderails, and side caster wheels extending transversely from the second pair of siderails; a central subassembly comprising first and second subassembly halves, and further comprising a first hinged connection between the first and second subassembly halves, a second hinged connection between the first subframe assembly and the first subassembly half, and a third hinged connection between the second subframe assembly and the second subassembly half, whereby the central subassembly allows the first and second subframe assemblies to be reconfigured between (a) an expanded configuration wherein the first and second subassembly halves are extended linearly and the first and second subframe assemblies are spaced a greater distance away from one another, and (b) a collapsed configuration wherein the first and second subassembly halves are folded against one another and the first and second subframe assemblies are spaced a lesser distance away from one another; and a platform repositionable between an elevated position when the first and second subframe assemblies are configured in the expanded configuration and a lower position when the first and second subframe assemblies are configured in the collapsed configuration.
 24. The convertible pushcart/scaffolding apparatus of claim 23, wherein the first subframe assembly, the second subframe assembly and the central subassembly bound an interior space having an open front in the expanded configuration, and wherein the platform is installable through the open front onto a selected corresponding pair of the first and second pluralities of rungs.
 25. The convertible pushcart/scaffolding apparatus of claim 24, wherein the first and second pluralities of rungs are affixed to interior sides of the first and second pairs of siderails respectively, and wherein the platform comprises first and second fins on opposite sides thereof for engaging the selected pair of rungs and allowing the platform to be installed by sliding into place along the selected pair of rungs. 